1. Field of the Invention
The invention relates to forming containers from flexible sheet material and, more particularly, to a method for forming such containers having inserts which have an effect on contents which may be disposed in a container and/or stiffen the container for display purposes.
2. Description of the Prior Art
A continuing problem in the packaging industry relates to forming containers from flexible sheet or film material containing elements or materials for affecting the product being packaged in a desired fashion and/or for enhancing the structural integrity of the final package.
One example of this kind of packaging problem occurs in the production of flexible container strips having inserted elements or materials for extending the shelf life of the packaged products. Although products susceptible to deterioration can be sealed inside containers under a vacuum or can be coated to resist deterioration prior to being placed in the container, it is apparent that these approaches involve a certain expenditure of time and effort and thus complicate packaging.
One approach, used for garment storage, was to construct a garment storage bag in which a fumigant could be disposed along with the garments. In one proposed garment bag, a foraminous pocket for holding a supply of moth repellant or insecticide was mounted within the bag; in another garment bag, a plurality of small containers filled with fumigant were attached to a board-like strip which, in turn, was affixed to a carrying frame within the bag. It is clear that these approaches were not effective for high-speed production, rough handling, or any number of other demands imposed upon modern containers.
Although insert materials suitable for acting on container contents in a desired manner already are known, present-day techniques for placing products into the containers along with the inserts do not lend themselves well to high-speed, efficient packaging. One proposal involved the use of container inserts impregnated with suitable materials such as corrosion-inhibitors, fumigants, etc. which could be inserted in the containers along with the products being packaged. A suitable anti-corrosion composition is disclosed by the Anti-Corrosion Patents referred to above. Another technique provided for attaching frangible ampules containing color-sensitive chemicals to a card and thereafter placing the card inside a container along with products to be sterilized. After the container and contents were sterilized and sealed, the ampules could be broken and the resultant color change (or lack of color change) indicated whether the contents were sterile. These approaches did not lend themselves well to high-speed production because the inserts tended to interfere with loading the products in the containers.
A concern in the packaging industry relates to displaying packaged products for public consumption in an appealing manner. Plastic bag-like packages of the character referred to are frequently constructed from transparent plastic film through which packaged products can be observed. When inserts of the character referred to above are mixed in with the products in such packages they can be seen by potential purchasers and they tend to reduce the appeal of the packages.
Another type of package insert element which has been used in the past is an advertizing sheet, or label, placed in the container with the products to identify the products, the manufacturer etc. These inserts, like those referred to previously, have made it difficult to achieve high rate packaging even though they may not be unsightly themselves. By printing labelling information on the container film itself, the production problems attendant loading packages with label inserts have been avoided in some circumstances.
The alternative practices of printing labels on the container film and inserting labels with the packaged product have not been effective to improve the appearance of packages of the sort referred to which are suspended from display racks, support hooks and so forth. Although these packages can be suspended from display racks simply by punching a hole through them, this type of approach tends to be undesirable because the package lacks structural strength. If the packaged products are relatively heavy the film packaging material tends to sag so that the labelling is obscured and the package appearance is poor. This approach is not even usable if it is desired to maintain a particular atmosphere within the container, that is, if a seal must be maintained for some reason.
In order to provide more readily supportable packages proposals have been made to divide the container into separate sections--one section for the container contents, and one section identified as a so-called header which can be punctured or to which external advertising or labeling material can be affixed for reinforcement. This construction permits the container contents to be isolated at all times and yet the header portion of the bag is stiff enough to permit the package to be suspended from a display rack.
Although the foregoing approach generally is effective, several improvements still are possible. For example, the external advertising material must be stapled or glued to the outside of the header and this presents problems vis-a-vis production speed and the security of the attachment. Among other things, stress concentrations can be developed if the attachment is not secure enough and the container may be ruined during handling or loading onto the display rack. Also, the external advertising material tends to increase the bulk of the finished container so that handling difficulties are increased and more space is required to display a given quantity of containers than otherwise is desired.
These problems may be overcome if the materials added to the header portion are disposed inside the header portion rather than being fastened to the outside of the header portion. Unfortunately, it is very difficult to process a container rapidly while at the same time placing an insert inside the header portion of the container.